Arkansas Senator Steve Faris (D-Malvern) has introduced SB 253, to move the primary (for president and all other office) to the 2nd Tuesday in August. Currently the presidential primary is in February and the primary for other office is in May, although the House has already passed a bill to put both in May.
It is quite unusual that any state legislator would propose a presidential primary in August. No state has ever held such a late presidential primary.